Effect of Organic Selenium on the Homeostasis of Trace Elements, Lipid Peroxidation, and mRNA Expression of Antioxidant Proteins in Mouse Organs.

(1) In this study we determined the effect of long-term selenomethionine administration on the oxidative stress level and changes in antioxidant protein/enzyme activity; mRNA expression; and the levels of iron, zinc, and copper. (2) Experiments were performed on 4-6-week-old BALB/c mice, which were given selenomethionine (0.4 mg Se/kg b.w.) solution for 8 weeks. The element concentration was determined via inductively coupled plasma mass spectrometry. mRNA expression of SelenoP, Cat, and Sod1 was quantified using real-time quantitative reverse transcription. Malondialdehyde content and catalase activity were determined spectrophotometrically. (3) After long-term SeMet administration, the amount of Se increased by 12-fold in mouse blood, 15-fold in the liver, and 42-fold in the brain, as compared to that in the control. Exposure to SeMet decreased amounts of Fe and Cu in blood, but increased Fe and Zn levels in the liver and increased the levels of all examined elements in the brain. Se increased malondialdehyde content in the blood and brain but decreased it in liver. SeMet administration increased the mRNA expression of selenoprotein P, dismutase, and catalase, but decreased catalase activity in brain and liver. (4) Eight-week-long selenomethionine consumption elevated Se levels in the blood, liver, and especially in the brain and disturbed the homeostasis of Fe, Zn, and Cu. Moreover, Se induced lipid peroxidation in the blood and brain, but not in the liver. In response to SeMet exposure, significant up-regulation of the mRNA expression of catalase, superoxide dismutase 1, and selenoprotein P in the brain, and especially in the liver, was determined.

A Comparative Evaluation of Antioxidant Activity of Extract and Essential Oil of Origanum onites L. In Vivo.

In the present study, the effects of Origanum onites L. extract and essential oil of O. onites L. on the antioxidant status of the liver and brain of mice were investigated. Due to certain disadvantages of essential oils, such as poor solubility, high volatility and sensitivity to UV light and heat, formulation of liposomes with Oregano essentials (OE) was optimized and used in this study. The results demonstrated that the best composition of the lipid carriers and OE were conducted in terms of the polydispersity index (PDI), mean particle size and encapsulation efficiency (EE). For further study the LE4 formulation was used, which contained Lipoid S100 at 45 mg, Lipoid S75 at 45 mg and 90 mg of EO. The administration of O. onites L. extract to mice for 21 days significantly decreased the glutathione (GSH) level in the livers and brains of the mice as well as the malondialdehyde (MDA) concentration in the livers. In the brains of the mice, MDA level significantly increased after this extract consumption. Whereas liposomes with OE significantly decreased GSH concentration in the mouse brain and MDA concentration in the mouse liver, there was an increased (p > 0.05) GSH level in the liver and MDA concentration in the brain of mice compared with the control group. It was found that both O. onites. ethanolic extract as well as liposomes with OE of this plant material affect the antioxidant status in the livers and brains of mice.

Elsholtzia ciliata (Thunb.) Hyl. Extracts from Different Plant Parts: Phenolic Composition, Antioxidant, and Anti-Inflammatory Activities.

Polyphenols play an important role on the health-promoting properties of humans. Plants belonging to Lamiaceae family are known as rich source of phenolic compounds. The current work aimed to evaluate the phenolic compounds, antioxidant, and anti-inflammatory activity of Elsholtzia ciliata (Thunb.) Hyl. ethanolic extracts from leaf, stem, flower, and whole herb. Twelve compounds were identified in ethanolic extracts using high-performance liquid chromatography (HPLC). The HPLC analysis revealed that chlorogenic acid, rosmarinic acid, and rutin were predominant compounds in ethanolicic extracts. Using HPLC-ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) post-column assay, avicularin, chlorogenic, and rosmarinic acids were identified as the predominant radical scavengers in all ethanolic extracts. All tested preparations significantly reduced the level of secretion of proinflammatory cytokines TNF-α, IL-6, and prostaglandin E2 induced by lipopolysaccharide treatment in mouse peritoneal macrophage cell culture. Stem and flower extracts were most efficient in reducing cytokine release, but leaf extract demonstrated stronger effect on prostaglandin E2 secretion. This is the first study exploring antioxidant efficiency by HPLC-ABTS post-column method and investigating anti-inflammatory activity of ethanolic extracts from E. ciliata different plant parts.

Natural Compounds Rosmarinic Acid and Carvacrol Counteract Aluminium-Induced Oxidative Stress.

Aluminum accumulation, glutathione (GSH) and malondialdehyde (MDA) concentrations as well as catalase (CAT) and superoxide dismutase (SOD) activities were determined in erythrocytes and brain and liver homogenates of BALB/c mice treated with Al3+ (7.5 mg/kg/day (0.15 LD50) as AlCl3 (37.08 mg/kg/day), whereas HCl (30.41 mg/kg/day) was used as Cl- control, the treatments were performed for 21 days, i.p., in the presence and absence of rosmarinic acid (0.2805 mg/kg/day (0.05 LD50), 21 days, i.g.) or carvacrol (0.0405 mg/kg/day (0.05 LD50), 21 days, i.g.). The treatment with AlCl3 increased GSH concentration in erythrocytes only slightly and had no effect on brain and liver homogenates. Rosmarinic acid and carvacrol strongly increased GSH concentration in erythrocytes but decreased it in brain and liver homogenates. However, AlCl3 treatment led to Al accumulation in mice blood, brain, and liver and induced oxidative stress, assessed based on MDA concentration in the brain and liver. Both rosmarinic acid and carvacrol were able to counteract the negative Al effect by decreasing its accumulation and protecting tissues from lipid peroxidation. AlCl3 treatment increased CAT activity in mice brain and liver homogenates, whereas the administration of either rosmarinic acid or carvacrol alone or in combination with AlCl3 had no significant effect on CAT activity. SOD activity remained unchanged after all the treatments in our study. We propose that natural herbal phenolic compounds rosmarinic acid and carvacrol could be used to protect brain and liver against aluminum induced oxidative stress leading to lipid peroxidation.

Post-exposure distribution of selenium and aluminum ions and their effects on superoxide dismutase activity in mouse brain.

The study was conducted to determine how aluminum (Al) and selenium (Se) ions alone and in combination affect superoxide dismutase (SOD) activity and to evaluate the distribution of these elements in the blood and the brain of laboratory mice. SOD activity in mouse brain was evaluated after single-time (within 24 h) and repeated (over 14 days) intraperitoneal (IP) injections of SeO32-, Al3+, and (SeO32-+Al3+) solutions. The control mice received IP injections of the same volume of saline. Aluminum concentration in mouse blood increased both after single-time and repeated injections of AlCl3 and the combined (AlCl3 + Na2SeO3) solutions. The concentration of Se increased in blood after single-time and repeated injections of Na2SeO3 and the combined (AlCl3 + Na2SeO3) solutions. After the single-time injection of the experimental solutions, the concentrations of both Al and Se in mouse brain remained at baseline, but after repeated injections of (AlCl3 + Na2SeO3) solutions increased aluminum concentration. A single IP injection of Al did not change SOD activity in mouse brain, while a single injection of Se or the Se + Al mixture decreased it. After 14 days, IP injections of Al or Se alone did not affect SOD activity, while their combination decreased it. Our results showed that Se ions decreased SOD activity in mouse brain after both single-time and repeated IP injections of selenium-containing solutions. The study failed to show a direct or linear effect of increased Al or Se concentrations on SOD activity in mouse brain.

Effect of Acanthopanax senticosus on the accumulation of cadmium and on the immune response of spleen cells.

Exposure to cadmium (Cd) is known to alter immune responses. Acanthopanax senticosus (Rupr. et Maxim.) Harms (AS) extract, an antioxidant-containing complex of phenolic compounds, tetracyclic triterpenoids/steroids, and polysaccharides, is known to produce Cd mobilization and excretion in vivo. Building upon earlier findings, the aim of the study was to evaluate the effects of an AS extract on Cd accumulation and changes in the presence of splenic immune cells in hosts during a chronic metal exposure. Chronic Cd exposure of BALB/c mice was induced by providing them solutions containing different levels of CdCl2 (25 or 250 mg/L) in double-distilled water, with/without a concurrent presence of AS root extract (approximately 151 g material/L), for 8 wk. At the study end, Cd levels in spleen were measured. Levels of key splenic immune cells, including macrophages, T-lymphocytes, and B-lymphocytes, were determined by immunohistochemistry using, respectively, CD68, CD3, and CD20 antibodies. The results indicated that chronic consumption of AS extract in the presence of the high dose of CdCl2 led to a significant decrease in Cd levels in mouse spleen. The effects of AS on the lower CdCl2 dose were less apparent. In addition, the presence of AS and Cd increased the amount of macrophages and both B and T lymphocytes in mouse spleen relative to concentrations that were lowered as a result of chronic metal only intake.

Relationship between Oxidative Stress and Left Ventricle Markers in Patients with Chronic Heart Failure.

Oxidative stress is proposed in the literature as an important player in the development of CHF and correlates with left ventricle (LV) dysfunction and hypertrophy in the failing heart. In this study, we aimed to verify if the serum oxidative stress markers differ in chronic heart failure (CHF) patients' groups depending on the LV geometry and function. Patients were stratified into two groups according to left ventricular ejection fraction (LVEF) values: HFrEF (<40% (n = 27)) and HFpEF (≥40% (n = 33)). Additionally, patients were stratified into four groups according to LV geometry: NG-normal left ventricle geometry (n = 7), CR-concentric remodeling (n = 14), cLVH-concentric LV hypertrophy (n = 16), and eLVF-eccentric LV hypertrophy (n = 23). We measured protein (protein carbonyl (PC), nitrotyrosine (NT-Tyr), dityrosine), lipid (malondialdehyde (MDA), oxidizes (HDL) oxidation and antioxidant (catalase activity, total plasma antioxidant capacity (TAC) markers in serum. Transthoracic echocardiogram analysis and lipidogram were also performed. We found that oxidative (NT-Tyr, dityrosine, PC, MDA, oxHDL) and antioxidative (TAC, catalase) stress marker levels did not differ between the groups according to LVEF or LV geometry. NT-Tyr correlated with PC (rs = 0.482, p = 0.000098), and oxHDL (rs = 0.278, p = 0.0314). MDA correlated with total (rs = 0.337, p = 0.008), LDL (rs = 0.295, p = 0.022) and non-HDL (rs = 0.301, p = 0.019) cholesterol. NT-Tyr negatively correlated with HDL cholesterol (rs = -0.285, p = 0.027). LV parameters did not correlate with oxidative/antioxidative stress markers. Significant negative correlations were found between the end-diastolic volume of the LV and the end-systolic volume of the LV and HDL-cholesterol (rs = -0.935, p < 0.0001; rs = -0.906, p < 0.0001, respectively). Significant positive correlations between both the thickness of the interventricular septum and the thickness of the LV wall and the levels of triacylglycerol in serum (rs = 0.346, p = 0.007; rs = 0.329, p = 0.010, respectively) were found. In conclusions, we did not find a difference in serum concentrations of both oxidant (NT-Tyr, PC, MDA) and antioxidant (TAC and catalase) concentrations in CHF patients' groups according to LV function and geometry was found. The geometry of the LV could be related to lipid metabolism in CHF patients, and no correlation between oxidative/antioxidant and LV markers in CHF patients was found.

Acute and Sub-Chronic Intraperitoneal Toxicity Studies of the Elsholtzia ciliata Herbal Extract in Balb/c Mice.

Elsholtzia ciliata essential oil (E. ciliata) has been reported to have an impact on the cardiovascular system. However, its toxicity remains unknown. Therefore, the objective of this investigation was to evaluate the toxicological aspects of the E. ciliata extract. Male Balb/c mice were subjected to either acute (a single dose administered for 24 h) or sub-chronic (daily dose for 60 days) intraperitoneal injections of the E. ciliata extract. The mice were assessed for blood hematological/biochemical profiles, mitochondrial functions, and histopathological changes. Additionally, in vitro cytotoxicity assessments of the E. ciliata extract were performed on immobilized primate kidney cells (MARC-145, Vero) and rat liver cells (WBF344) to evaluate cell viability. The control groups received an equivalent volume of olive oil or saline. Our results demonstrated no significant detrimental effects on hematological and biochemical parameters, mitochondrial functions, cellular cytotoxicity, or pathological alterations in vital organs following the intraperitoneal administration of the E. ciliata extract over the 60-day sub-chronic toxicity study. In general, E. ciliata displayed no indications of toxicity, suggesting that the E. ciliata extract is a safe natural product with a well-defined therapeutic and protective index (found to be 90 and 54, respectively) in Balb/c mice.

Effect of Selenium on the Iron Homeostasis and Oxidative Damage in Brain and Liver of Mice.

Selenium is an essential trace element that maintains normal brain function, mainly due its antioxidant properties. Although the amount of Se in the body is tightly regulated by the liver, both an excess of and deficiency in Se can modulate the cellular redox status and affect the homeostasis of other essential elements for both humans and animals. The aim of this study was to determine the effect of inorganic selenium excess on oxidative stress and iron homeostasis in brain and liver of laboratory BALB/c mice, which were supplemented with Na2SeO3 solution (0.2 mg and 0.4 mg Se/kg body weight) for 8 weeks. The content of the lipid peroxidation product malondialdehyde and antioxidant enzyme catalase activity/gene expression were used as markers of oxidative damage and were evaluated by spectrophotometric assays. Selenium and iron concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS). Catalase gene expression was analyzed by qRT-PCR and ΔΔCt methods. Our results showed that doses of 0.2 mg Se and 0.4 mg Se caused a relatively low accumulation of Se in the brain of mice; however, it induced a 10-fold increase in its accumulation in the liver and also increased iron accumulation in both tested organs. Both doses of Se increased the content of malondialdehyde as well as decreased catalase activity in the liver, while the 0.4 mg Se dose has also activated catalase gene expression. Brain of mice exposed to 0.2 mg Se showed reduced lipid peroxidation; however, the exposure to 0.4 mg of Se increased the catalase activity as well as gene expression. One may conclude that exposure to both doses of Se caused the accumulation of this micronutrient in mice brain and liver and have also provided a disrupting effect on the levels of iron. Both doses of Se have triggered oxidative liver damage. In the brain, the effect of Se was dose dependent, where -0.2 mg of Se provided antioxidant activity, which was observed through a decrease in lipid peroxidation. On the contrary, the 0.4 mg dose increased brain catalase activity as well as gene expression, which may have contributed to maintaining brain lipid peroxidation at the control level.

The Effects of Cannabis sativa L. Extract on Oxidative Stress Markers In Vivo.

In recent decades, a lot of attention has been paid to Cannabis sativa L. due to its useful applications, including in fibers, oil, food for humans and animals, and therapeutics. The present study aimed to determine antioxidant activity of cannabinoids in Cannabis sativa L. in vivo, evaluating the possible antioxidative effect of Cannabis sativa L. extract (CE) on malondialdehyde (MDA) and glutathione (GSH) concentrations as well as on catalase (CAT) activity in BALB/c mice. In total, 40 mice were divided into five equal groups: the aluminum group (7.5 mg AlCl3/kg/d (0.15 LD50), the saline group, the 10% ethanol group (an appropriate amount of the solution for mouse weight), the CE group (1.6 mg CE/g/day), and the aluminum-CE group (7.5 mg AlCl3 plus 1.6 mg CE/g/day). The results of the study showed that CE significantly decreased (by 26.81%, p < 0.05) the concentration of GSH in blood of the mice and the concentration of MDA in the brain (by 82.12%) and liver (by 53.5%) of the mice compared to the respective concentrations in the AlCl3 group. CE significantly (p < 0.05) increased CAT activity in the brain (by 64.79%) and liver (by 72.37%) of the mice after the AlCl3-induced prooxidant effect. The results showed the antioxidant activity of cannabidiolic acid (CBDA) in vitro. The findings in vivo indicate that Cannabis sativa L. is a good source of natural antioxidants and can be used in the management of oxidative stress.

Virus Mimetic Poly (I:C)-Primed Airway Exosome-like Particles Enter Brain and Induce Inflammatory Cytokines and Mitochondrial Reactive Oxygen Species in Microglia.

Viral infections induce extracellular vesicles (EVs) containing viral material and inflammatory factors. Exosomes can easily cross the blood-brain barrier during respiratory tract infection and transmit the inflammatory signal to the brain; however, such a hypothesis has no experimental evidence. The study investigated whether exosome-like vesicles (ELVs) from virus mimetic poly (I:C)-primed airway cells enter the brain and interact with brain immune cells microglia. Airway cells were isolated from Wistar rats and BALB/c mice; microglial cell cultures-from Wistar rats. ELVs from poly (I:C)-stimulated airway cell culture medium were isolated by precipitation, visualised by transmission electron microscopy, and evaluated by nanoparticle analyser; exosomal markers CD81 and CD9 were determined by ELISA. For in vitro and in vivo tracking, particles were loaded with Alexa Fluor 555-labelled RNA. Intracellular reactive oxygen species (ROS) were evaluated by DCFDA fluorescence and mitochondrial superoxide-by MitoSOX. ELVs from poly (I:C)-primed airway cells entered the brain within an hour after intranasal introduction, were internalised by microglia and induced intracellular and intramitochondrial ROS production. There was no ROS increase in microglial cells was after treatment with ELVs from airway cells untreated with poly (I:C). In addition, poly (I:C)-primed airway cells induced inflammatory cytokine expression in the brain. The data indicate that ELVs secreted by virus-primed airway cells might enter the brain, cause the activation of microglial cells and neuroinflammation.

Apoptosis is activated in an early period after radiofrequency ablation of liver tissue.

BACKGROUND/AIMS: Hyperthermia induced apoptosis may lead to tumor cell death thus expanding the volume of non-viable tissue and warrant a "safety margin" of at least 10mm to exclude the possibility of tumor recurrence. We carried out an experimental study to investigate the cellular injury produced by radiofrequency ablation in the area surrounding the ablated tissue and to describe early apoptotic processes in the transition zone following radiofrequency ablation procedure in a porcine liver model. METHODOLOGY: Nine anesthetized pigs underwent laparotomy and local thermal ablation of the liver parenchyma. The ablated tissue and the surrounding parenchyma were investigated for apoptosis applying Western blot analysis and immunohistochemistry. RESULTS: The active (cleaved) caspase-3 17-kDa subunit was detected in the transition zone one hour after ablative procedure at a distance of 9-10 mm from the rim of the necrosis zone. In contrast analysis of tissues in necrosis zone and in surrounding normal liver parenchyma revealed no markers of apoptotic activity. CONCLUSION: We determined that apoptosis, leading to further cell death, is activated in the majority of cells in the transition zone, thus supporting the hypothesis that the "safety margin" of 10 mm is encompassed by the indirect thermal effect.

Acute toxicity of ibogaine and noribogaine.

OBJECTIVE: To evaluate acute toxic effect of ibogaine and noribogaine on the survival of mice and determine median lethal doses of the substances mentioned. MATERIAL AND METHODS: White laboratory mice were used for the experiments. Ibogaine and noribogaine were administered intragastrically to mice via a stomach tube. Control animals received the same volume of saline. The median lethal dose was calculated with the help of a standard formula. RESULTS: To determine the median lethal dose of ibogaine, the doses of 100, 300, 400, and 500 mg/kg were administered intragastrically to mice. The survival time of mice after the drug administration was recorded, as well as the number of survived mice in each group. Upon administration of ibogaine at a dose of 500 mg/kg, all mice in this dose group died. Three out of four mice died in the group, which received 300 mg/kg of ibogaine. No mouse deaths were observed in the group, which received 100 mg/kg of ibogaine. The determined LD(50) value of ibogaine equals to 263 mg/kg of body mass. In order to determine the median lethal dose of noribogaine, the doses of 300, 500, 700, and 900 mg/kg were administered to mice intragastrically. Noribogaine given at a dose of 500 mg/kg had no impact on the mouse survival. The increase of noribogaine dose to 700 mg/kg of mouse body mass led to the death of three out of four mice in the group. Upon administration of noribogaine at a dose of 900 mg/kg, all mice in this group died. The LD(50) value of noribogaine in mice determined on the basis of the number of dead mice and the size of the doses used equals to 630 mg/kg of mouse body mass. The behavior of mice was observed upon administration of ibogaine or noribogaine. Low doses of ibogaine and noribogaine had no impact on the mouse behavior. External effects (convulsions, nervous behaviour, limb paralysis) were observed only when substances were administrated at higher doses. CONCLUSIONS: It has been determined that the median lethal dose of ibogaine and noribogaine equals to 263 mg and 630 mg/kg of mouse body mass, respectively. The toxicity of ibogaine is 2.4 times higher than that of noribogaine.

Subacute effects of cadmium and zinc ions on protein synthesis and cell death in mouse liver.

OBJECTIVE: The aim of this study was to evaluate in vivo the effects of cadmium and zinc ions on translational machinery and death of mouse liver cells. MATERIAL AND METHODS: Outbred mice received intraperitoneal injections of cadmium chloride solution (1.4 micromoles cadmium per 1 kg of body weight) and/or zinc sulfate solution (4.8 micromoles zinc per kg of body weight) three times per week for six weeks. Analogical volume of saline solution was injected to the control mice. Protein synthesis was evaluated by incorporation of [(14)C]-labeled leucine into peptides and proteins. Total tRNAs were isolated using deproteinized extract of liver tissue. Postmitochondrial supernatant was as a source of leucyl-tRNA synthetase. Activities of tRNA(Leu) and leucyl-tRNA synthetase were measured by an aminoacylation reaction using [(14)C]-labeled leucine. Liver cell apoptosis was detected by TUNEL assay using in situ cell death detection kit. RESULTS: A decrease in incorporation of [(14)C]-labeled leucine into proteins was detected in liver, kidney, and heart as well as diminution of tRNA(Leu) acceptor activity in cadmium-exposed liver. Cadmium caused activation of the leucyl-tRNA synthetase and induced liver cell apoptosis. Pretreatment of mice with zinc sulfate solution favored to protection of protein synthesis and acceptor activity of tRNA(Leu) against cadmium-induced inhibition. Under co-exposure of mouse liver to cadmium and zinc, activity of the leucyl-tRNA synthetase was at the level of control. Zinc did not influence TUNEL-positive cell number in cadmium-exposed mouse liver. CONCLUSIONS: Under subacute intoxication of mice by cadmium, zinc ions protect the translation machinery against inhibition, but do not decrease the number of apoptotic cells in the liver.

The Effects of Buckwheat Leaf and Flower Extracts on Antioxidant Status in Mouse Organs.

This study was undertaken to investigate the effects of the extracts of buckwheat leaf and flower on the antioxidant status of the brain and liver tissue. The administration of buckwheat extracts (both concentrations were 10%) to mice (at the dose 10 mL/kg of body weight) for 21 days significantly decreased superoxide dismutase (SOD) activity and reduced the amount of glutathione (GSH) and malondialdehyde (MDA) in the mouse brain, while catalase (CAT) activity significantly increased. In the mouse liver, the amount of GSH and activity of SOD increased, while the CAT activity after administering buckwheat leaf and flower extracts was lower in experimental mice than in the control group. However, the administration of 10% ethanol (for 21 days) to control animals also had a significant effect on the antioxidant system in brain and liver cells. Experimental animals demonstrated rather marked changes in the activities of the antioxidant enzymes SOD and CAT in their liver and brain cells, and changes in the levels of GSH and MDA were observed when compared with the control group.

Assessment of the effect of Echinacea purpurea (L.) Moench on apoptotic and mitotic activity of liver cells during intoxication by cadmium.

Cadmium (Cd(2+)) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. Cd(2+) is toxic to a wide range of organs and tissues, however, the primary target organs of Cd(2+) toxicity are the liver and kidney. Echinacea purpurea stimulating one or another tread of the immune system stimulates the expression of immunoglobulins and interferons. The experiments were performed on white laboratory mice using intraperitoneal (i.p.) injections 0.05 LD(50) amount of CdCl(2) solution. Two groups of mice were injected by Echinacea purpurea liquid extract: one 0.05 LD(50) and the other 0.1 LD(50). In this article, the Cd(2+) distribution in internal organs, its effect on the mitotic and apoptotic activity of liver cells, as well as effects of Echinacea purpurea liquid extract on Cd(2+)-induced changes in mice were investigated. Cd(2+) concentration in mice blood, liver, and kidney was detected by atomic absorption spectroscopy. Long-term injections of extract of Echinacea purpurea combined with Cd(2+)Cl(2) leads to the significant increase of Cd(2+) concentration in blood and investigated organs of experimental mice. Mitotic and apoptotic activity of liver cells was expressed as the estimated number of mitotic and apoptotic liver cells in randomly selected reference areas in histological slide. Echinacea purpurea decreases the mitotic activity of liver cells induced by Cd(2+) and increases apoptotic activity of the liver cells.

Influence of Echinacea purpurea (L.) Moench extract on the toxicity of cadmium.

Echinacea purpurea (L.) Moench (EP) has many beneficial features, especially strengthening the immune system. Cadmium (Cd) is a ubiquitous metal and cumulative poison that may cause liver and kidney damage and the formation of neoplasia. In this article, the changes in organs and metabolism, the accumulation of various levels of Cd in tissues, and the effects of EP liquid extract on Cd-induced changes in mice were investigated. Experiments were carried out on the white laboratory mice. Solution of different Cd and EP concentrations were given to drink and experiments were performed. The concentration of Cd in mice blood, liver, kidneys, heart, spleen, skeletal muscle was determined using an electrothermal graphite furnace atomic absorption spectrophotometer Perkin-Elmer/Zeeman 3030. Long time per os of extract of EP combined with Cd leads to a significant increase of Cd concentration in blood and investigated organs of experiment mice.

Effects of cadmium ions on the initial stage of translation and the cell death in mouse liver.

OBJECTIVE: To evaluate in vivo and in vitro effects of cadmium ions on the activities of mice liver tRNA(Leu)and leucyl-tRNA synthetase and on the type of liver cells death. MATERIAL AND METHODS: White laboratory mice were intoxicated by intraperitoneal injection of cadmium chloride solution (1.6 mg cadmium ions/1 kg of body weigh). Total tRNAs were isolated by adding ethanol and isopropanol into the phenol-deproteinized supernatant of mouse liver homogenate. Post-mitochondrial fraction of the liver cells was used as a source of leucyl-tRNA synthetase. Acceptor activity of tRNA(Leu)and activity of leucyl-tRNA synthetase were measured in tRNA aminoacylation reaction with [14C]-labeled leucine as a substrate. An apoptotic cell death was assessed by the TUNEL assay using in situ cell death detection kit. DNA degradation was verified by electrophoresis. RESULTS: It was determined that 2-24 hours after intoxication with sublethal dose of cadmium ions the acceptor activity of mice liver tRNA(Leu)was decreased by 43-73% as compared to control. At the same time intervals, the activity of leucyl-tRNA synthetase was reduced about 20-30%. Experiments in vitro revealed that 10-20 microM concentrations of cadmium ions suppressed the activities of mice liver tRNA(Leu)and leucyl-tRNA synthetase by 40-98%. No significant difference was observed between the number of TUNEL positive apoptotic liver cells in the control mice and 24 hours after intoxication with cadmium chloride. Electrophoresis revealed extensive degradation of nuclear DNA. CONCLUSIONS: Cadmium ions significantly reduce activities of tRNA(Leu)and leucyl-tRNA synthetase in vivo and in vitro. There is no significant difference between the number of apoptotic cells in the control liver specimens and in those after 24 hours of intoxication with cadmium chloride. In latter specimens DNA electrophoresis revealed as extensive degradation of DNA, which is characteristic to the cell necrosis.

Effects of cadmium and zinc ions on mitotic activity and protein synthesis in mouse liver.

OBJECTIVE: To evaluate the in vivo effects of cadmium and zinc ions on mitotic activity and protein synthesis in mouse liver. MATERIAL AND METHODS: White outbred mice were injected intraperitoneally with cadmium chloride solution (14 micromoles cadmium per 1 kg of body mass) and/or with zinc sulfate solution (48 micromoles zinc per 1 kg of body mass). Histological slides were examined by light microscopy. For each specimen, the number of mitotic cells was counted in 10 randomly selected reference areas. Protein synthesis was evaluated by incorporation of [14C]-labeled leucine into newly synthesized peptides and proteins. RESULTS: We found that the mitotic index of mouse liver cells was increased for periods of 2-8 h after cadmium chloride injection; after 24 h the mitotic index significantly diminished. These data indicate a possible increase in liver cell regeneration during the initial 8 h following acute cadmium exposure. Zinc ions did not affect liver mitotic activity, and, interestingly, decreased the mitotic index in the liver of cadmium-treated mice to control levels. An examination of the kinetics of protein synthesis in mouse liver over a 24 h period after cadmium chloride injection revealed that incorporation diminished by 38% at 2 h, then increased 51% by 8 h and again decreased by 32% at 24 h as compared to control. Zinc ions increased protein synthesis in mouse liver 8 h after zinc sulfate injection. In assessing the effects of cadmium and zinc ions in vivo, it appeared that zinc ions tended to protect protein synthesis in response to cadmium ions but only at 2 h after cadmium intoxication. CONCLUSIONS: Zinc ions are capable of normalizing an increase in the mitotic index of liver cells at the early stage of cadmium poisoning (up to 8 h) and to protect the liver translation machinery against inhibition by cadmium.

The effects of zinc ions on activities of tRNALeu and leucyl-tRNA synthetase of mice liver.

UNLABELLED: The aim of this study was to examine the effects of zinc ions on activities of tRNA(Leu) and leucyl-tRNA synthetase of mice liver. MATERIAL AND METHODS: White laboratory mice (20-25 g) were used for study purposes. Animals were intoxicated with ions of zinc by injection of 0.15 LD50 dose of zinc sulphate solution (1.56 mg Zn2+ per 1 kg of body weight) into abdominal cavity. After 8 hours, preparations of total tRNA and aminoacyl-tRNA synthetases were isolated from the intoxicated and normal (control) mice liver. Acceptor activity of tRNA(Leu) and activity of leucyl-tRNA synthetase were determined in tRNA aminoacylation reaction using [14C]-labeled leucine. Actions of zinc ions on acceptor activity of tRNA(Leu) and on activity of leucyl-tRNA synthetase from liver of control animals in vitro were determined after addition into reaction mixture different concentrations of zinc sulphate solution. RESULTS: It was determined that acceptor activity of mice liver tRNA( Leu)8 hours after intoxication with zinc ions has increased by 29% and activity of leucyl-tRNA synthetase has increased by 20% as compared to control. Experiments in vitro have shown that 5-20 microM concentrations of zinc ions in reaction mixture stimulate the acceptor activity of mice liver tRNA(Leu)by 18-30%, higher concentration of zinc ions (40 microM)--suppresses it by 26%. The study of leucyl-tRNA synthetase activity in vitro has shown that 5-10 microM concentrations of zinc ions in reaction mixture increase activity of this enzyme by 11-16%, higher concentrations of zinc ions (20-40 microM)--decrease it by 13-21%. CONCLUSIONS: After 8-hour intoxication with zinc ions the activities of both studied components of the translation machinery--tRNA(Leu) and leucyl-tRNA synthetase were increased. It may be connected with the stimulation of zinc-binding metallothionein synthesis which is involved in the detoxification of heavy metals. Low concentrations of zinc ions in reaction mixture increase tRNA(Leu) and leucyl-tRNA synthetase activities; higher concentrations of these ions decrease activity of those components of protein synthesis system. The results show that zinc ions directly act on the activities of both components of translation machinery.